Arc Fault Circuit Interrupter

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1 Arc Fault Circuit Interrupter Pillar To Post Increasing Electrical Fire Safety An arc fault circuit interrupter, or AFCI, is a new type of circuit breaker designed to detect sparking in an electrical system, and to shut down the affected circuit before it causes a fire. The jury is still out on whether AFCIs actually save lives and property. A household circuit can cause fire in two ways: circuit overload and sparking. Standard circuit breakers or fuses usually protect an overloaded circuit, but the breakers may not trip from intermittent sparking. For example, if you pierce or sever an electrical cable while hammering a nail into a wall, you could create an intermittent short, resulting in sparking. If the breaker does not trip, a fire could start. The AFCI is designed to detect such problems. Other potential causes of sparking: A frayed extension cord A squeezed or pinched cord Old and cracked insulation on electrical wires and cables Loose electrical connections What s the Difference Between an AFCI and a GFCI? A GFCI, or a ground-fault circuit interrupter, is typically installed in areas with a high risk for electrical shock, such as bathrooms (see Pillar To Post GFCI Info Series). A GFCI protects people from electric shock, while an AFCI protects homes from electrical fires. What Do These Devices Look Like? Where Are They Installed? An AFCI fits into the electrical panel in place of a standard circuit breaker. It looks like a GFCI breaker except the AFCI has a blue test button while the GFCI has an orange test button. AFCIs are becoming mandatory in some jurisdictions. In 2002, the National Electrical Code insisted on AFCIs for all bedroom electrical outlets and their branch circuits. Information Series 2007 Pillar To Post Inc.

2 AFCIs may be retrofitted to any home with a modern circuit breaker panel. But before you ask your electrician to replace all your breakers with AFCIs, consider the following: AFCIs are expensive, about $40 to $60 dollars per breaker. For a typical panel, you might pay a sum of $1,500, not including labor. AFCI breakers may not be available for an old panel. Can an AFCI Make an Old Electrical System Safer? Old wiring has likely been subjected to years of modifications and abuse, making it a more likely candidate for sparking. Insurance companies are concerned about the safety of knob and tube wiring in particular, making an AFCI seem an ideal retrofit. But since AFCIs have not been tested with old wiring, certifying laboratories and electrical authorities cannot yet assure the public that AFCIs will perform as expected. Not Quite Electrical Nirvana It will take several more years before statistics reflect anything concrete about how well AFCIs function. In the meantime, we can only assume that AFCIs reduce the chances of electrical spark-induced fires. Electrical authorities do plan, however, to ultimately mandate every breaker in your electrical panel as an AFCI or a GFCI, or a device that covers both, protecting people from electric shock and homes from electrical fires. Pillar To Post encourages anyone who feels they would benefit from AFCIs to consult an electrician. We would like to make one thing clear: we do not believe AFCIs are a quick fix for dangerous wiring, nor are they an excuse to live with an unsafe electrical system. A qualified electrician should promptly deal with unsafe wiring conditions. Pillar To Post, Austin Texas Team TREC 6056 Locally Owned and Operated since 2002 We welcome your comments and suggestions for future Information Series topics austinnorth@pillartopost.com (512)

3 Ground Fault Circuit Interrupter A ground fault circuit interrupter, or GFCI, is an inexpensive electrical safety device that can protect you and your family members from a serious electric shock. Pillar To Post Have you ever had an electric shock? While it is an unpleasant experience, it is not usually fatal. However, given the right conditions, the same shock could be fatal! If your body makes a solid connection to the ground, the shock could easily kill you. Here are two examples of a solid ground connection: If you are physically standing or touching the ground outside If you touch something conductive, such as any part of the plumbing system in your house, that is also touching the ground outside In other words, if you decide to operate your hedge trimmer in your bare feet and you get a shock, you may not survive it. How Can a GFCI Help? A GFCI is a special electrical outlet that prevents electric shocks in situations such as the ones described above. The GFCI monitors the electrical current leaving from and returning to the outlet. The current leaving the outlet should be the same amount as the returning current. If the current returning is less than that which leaves, the missing current could be passing through somebody s body to the ground. The GFCI detects the mismatch and shuts off the electrical outlet in a split second. Where Should GFCI Outlets Be Located? GFCI outlets should be installed in any area that presents a risk of an electric shock withg a direct path to the ground. In other words, anywhere you might directly touch the ground outside or anywhere where you might touch a part of the plumbing system. Some smart GFCIs locations are: Exterior outlets Kitchen counter outlets (not common in Canada) Bathroom outlets Garage outlets Outlets in unfinished basements Information Series 2007 Pillar To Post Inc.

4 This is not a complete list. Areas near swimming pools, hot tubs, and so on should also include this type of outlet. GFCIs are not perfect, however, and have been known to nuisance trip when connected to certain types of electrical equipment. For this reason, exceptions to the suggested (or required) locations for GFCIs exist. For example, a regular outlet would be a better choice for a freezer in your garage since the potential for nuisance tripping of the GCFI is high and might go undetected for days, leading to spoiled food in the shut-off freezer. Remote GFCI Several electrical outlets usually connect to a single circuit in an average home. A single GFCI outlet will protect all of the outlets in the circuit, even if the other outlets are not GFCIs. But the GFCI outlet must be the first outlet in the string in order for it to properly protect the other outlets, and, of course the connections have to be properly made. Remote GFCIs sometimes cause confusion for home owners in the following ways: A home owner thinks the bathroom does not have a GFCI because the outlet looks like a standard one. The standard outlet under the protection of a remote GFCI should have a sticker indicating its GFCI protection. The problem is, the sticker does not stick forever. A Pillar To Post inspector can test this for you. A standard outlet that does not appear to work in a bathroom or kitchen may actually be attached to a remote GFCI outlet that has nuisance tripped. Before calling an electrician, check the GFCI outlets in other bathrooms and in other locations around the house. Testing GFCIs are easy to test and should be tested every month. Simply press the test button on the outlet. You should hear a pop as the reset button pops out a little. To reset, just press the reset button. If the GFCI fails to trip, or if you are unable to reset it, it is time for an electrician to replace it. Special breakers also provide GFCI protection to the entire circuit. These breakers can be installed instead of GFCI outlets. The GFCI breaker should also be tested monthly. You will recognize this breaker from the test and reset button. GFCIs can help prevent injury and death from electric shock. It is a small device worth having to ensure the safety of your family members. Pillar To Post, Austin Texas Team TREC 6056 Locally Owned and Operated since 2002 We welcome your comments and suggestions for future Information Series topics austinnorth@pillartopost.com (512)

5 Pillar To Post Electrical Outlet Problems The electrical outlet not only provides vital access to the electrical current that makes your house hum, but it also warrants deeper consideration for reasons of comfort and safety. Our Pillar To Post inspectors have seen it all when it comes to incorrect outlet wiring, a safety hazard if left unattended. But before we discuss safety measures, let s start with a quick tour of this component and its mate, the plug. Have you ever wondered why your electrical outlets have holes of different sizes and shape? To accommodate the plug is the obvious answer. But there is more to this relationship than meets the eye. Hidden behind the outlet is a series of wires that must be properly connected for the outlet s safe functioning. On a modern electrical outlet that accommodates a three-pronged plug, each hole serves a specific purpose: the round hole is for the ground pin on the plug; the small slot takes the small blade on the plug and connects to the hot wire in the outlet (the wire that can cause a shock); the large slot takes the large blade and connects to the neutral wire in the outlet. Specific wires have to be connected to the proper terminals for an outlet s safe function. Correct installation is so important that our Pillar To Post inspectors spot-check outlets with an outlet tester during every inspection. Reverse Polarity The large slot and small slot on an electrical outlet, and the different-sized blades on a plug, designate their respective polarizations, and ensure that the plug goes in the outlet only one way, a safety feature that reduces the chances of shock. For instance, a light-bulb socket has exposed electrical connections, the threads being the most exposed part. But polarized socket threads are attached to the neutral wire to prevent someone from getting a shock when changing a light bulb. If the electrical outlet itself is mis-wired with reverse polarity, the lamp socket threads described above will become hot. If you touch the threads in the socket, or on the bulb as you screw it into the socket, you may get a shock. Information Series 2007 Pillar To Post Inc.

6 Outlet Not Grounded Pillar To Post inspectors have also discovered outlets with the circular ground holes but with no ground wire connected. In older homes, sometimes the cable leading to the outlet does not have a ground wire, yet the outlet has nonetheless been upgraded to a modern grounded type. Some plug-in electrical devices need this ground connection for their built-in safety features. If the outlet appears to be grounded but is not, the device s safety features will not work. Old Outlets In older homes some outlets may have no ground slot at all. This does not represent a defect or safety concern, but you will not be able to plug in an electrical appliance that has a ground pin on the plug. Today, most plug-in appliances are not the grounded style and, therefore, do not use or have a ground pin on the plug because they are a double insulated design. In these cases, the old ungrounded outlet will work fine. If you think it might be a good idea to simply cut off the ground pin to accommodate an outlet without a ground hole, think again. This procedure is doubly unsafe because it not only bypasses the grounding safety feature, but also it bypasses the polarizing feature since a de-pinned plug can be inserted into the outlet either way. Easy to Fix An electrician can fix these outlet problems. Though your outlets may appear as minor considerations in the grand scheme of your home, your understanding and the safe installation of your outlets can prevent serious safety hazards. Pillar To Post, Austin Texas Team TREC 6056 Locally Owned and Operated since 2002 We welcome your comments and suggestions for future Information Series topics austinnorth@pillartopost.com (512)

7 Aluminum Branch-circuit Wiring If you ask three electricians about the uses and safety of aluminum wiring, you will likely get at least three different answers. Furthermore, opinion varies again depending on where you live in North America. The more you research into aluminum wiring, the more frustrated you may become. We hope this article will clear up any confusion and end the frustration. Pillar To Post What s the Problem with Aluminum Wiring? From the mid 60s to the late 70s, aluminum wire often replaced copper as a less expensive alternative. Aluminum, however, is not a direct replacement for copper since each type of wire has different physical properties. Aluminum s properties proved problematic for reasons no one had anticipated. What you need to know is the following: with aluminum wiring it is possible that, over time, a high resistance connection and/or arcing could develop somewhere in the electrical system, resulting in a connection that gets very hot and increases risk of fire. Fortunately, the problems associated with aluminum wiring are now well understood, thus shifting the focus to rendering existing installations safe. A knowledgeable electrician with aluminum wiring experience can check for safety and fix what needs fixing. Solutions Re-wire the Home If you are renovating, or the configuration of your home is such that stringing new wiring is relatively easy, re-wiring your home may be a good idea. In most cases, however, re-wiring is an expensive and disruptive undertaking. COPALUM Crimp Connection COPALUM is a proprietary system that involves crimping a copper wire to existing aluminum wire using a special crimp connection tool that exerts extremely high pressure on the joint. This kind of connection is called cold welding. The copper wire is then connected to fixtures and outlets, etc. Once you convert the aluminum to copper with the cold-weld method, the repair is considered permanent. This solution, however, is expensive and requires an electrician certified in this system. Information Series 2007 Pillar To Post Inc.

8 Pigtail Repair Similar to the COPALUM connection described above, the pigtail repair method involves attaching copper wire to the existing aluminum. Pigtailing uses special twist connectors compatible with both aluminum and copper. While the pigtailing parts are inexpensive and readily available, the pigtailing technique requires specialized knowledge and experience. Furthermore, although pigtailing is cheaper than the COPALUM system, its success depends entirely on how well the electrician executes the repair. It is difficult to get a good connection that will not oxidize, making long term safety an issue. Some believe that a poorly executed pigtail is worse than doing nothing. In some geographical areas, pigtailing is not considered an acceptable solution. Retrofit all Connections with Aluminum Compatible Devices Standard electrical outlets and light switches are not compatible with aluminum wiring. Fortunately, tested and approved replacement devices and connectors are available from electrical supply shops. Some devices, however, such as ceiling-mounted light fixtures not rated for aluminum wire, still require an electrician who knows the pigtailing technique. A Few More Points In 1972, a new aluminum alloy, and aluminum-compatible devices, entered the market. Homes wired with aluminum after 1972 are more likely to have this new aluminum. This new aluminum solved many of the problems associated with the original aluminum wiring. These homes, however, still require an experienced electrician for a wiring retrofit. Also, generally speaking, the problems associated with aluminum wiring have to do with branch-circuit wiring smaller than 8 gauge. Anything 8 gauge and higher, such as wiring for a dryer or stove, does not present a problem. Most important to remember: if you have aluminum wiring, a licensed and experienced electrician should perform all electrical work. The Best Course of Action Since even amongst electricians misinformation and confusion persist, an electrician with specific knowledge and experience should evaluate each home on a case-by-case basis. The good news is, aluminum wiring can be made safe, but seek the advice of an expert. Pillar To Post, Austin Texas Team TREC 6056 Locally Owned and Operated since 2002 We welcome your comments and suggestions for future Information Series topics austinnorth@pillartopost.com (512)